Problem 3
Draw structural representations of the functional groups in the following types of compound: (a) amine; (b) alcohol; (c) carboxylic acid; (d) ether; (e) ester; (f) thiol; (g) chloroalkane; (h) nitro compound; (i) alkyne; (j) aldehyde; (k) ketone; (l) amide.
Problem 8
Draw structural formulae for the following compounds: (a) octane; (b) 2 -methylpentane; (c) 3 -ethylheptane (d) 2,2 -dimethylpropane.
Problem 9
Draw structural formulae for the following alkenes and distinguish between \((E)\) - and \((Z)\) -isomers where appropriate: (a) hex-3-ene; (b) but-2-ene; (c) pent-l-ene; (d) 3,4 -dimethylhept- 3 -ene.
Problem 12
Draw the structures of the following compounds and identify the types of \(C\) centre (primary, secondary, tertiary or quaternary): (a) butane; (b) 2 -methylpentane; (c) 2,2,4,4 -tetramethylhexane (d) 3 -ethylpentane.
Problem 16
\(2,3-\) Dibromopentane has the structure: Explain why this compound has enantiomers and diastereoisomers.
Problem 18
What isomers do the following molecules possess? Consider only acyclic structures. (a) \(\mathrm{C}_{4} \mathrm{H}_{10}\) (b) \(\mathrm{C}_{4} \mathrm{H}_{9} \mathrm{Cl}\) (c) \(\mathrm{C}_{4} \mathrm{H}_{6}\) (d) \(\mathrm{C}_{4} \mathrm{H}_{8} \mathrm{Cl}_{2}\)
Problem 24
A compound A (which has a foul smell) shows a parent ion in its mass spectrum at \(m / z\) 76. The \(^{1} \mathrm{H}\) NMR spectrum of A shows signals with relative integrals as follows: \(\delta 2.10\) (singlet, \(3 \mathrm{H}\) ), 2.53 (quartet, \(2 \mathrm{H}\) ), 1.27 (triplet, \(3 \mathrm{H}\) ) ppm. The \(^{13} \mathrm{C}\) NMR spectrum exhibits three resonances. Elemental analysis for A gives \(\mathrm{C} 47.3, \mathrm{H} 10.6 \%\) Compound \(\mathbf{B}\) is an isomer of \(\mathbf{A}\) and also has a foul smell; \(\mathbf{B}\) also has three signals in its \(^{13} \mathrm{C}\) NMR spectrum. Suggest identities and structures for \(\mathbf{A}\) and B.
